The present invention relates to an absorbent article mainly used in incontinence pads, sanitary napkins, vaginal discharge sheets, medical pads, toiletry goods, and disposable diapers, and particularly relates to an absorbent article in which a recessed groove is formed along a longitudinal direction on a from surface.
Absorbent articles having an absorber interposed between an impermeable back surface sheet such as a polyethylene sheet or a polyethylene sheet laminated nonwoven fabric and a permeable front surface sheet such as a nonwoven fabric or a permeable plastic sheet have been known.
Various improvements have also been added to this kind of absorbent article and various kinds of absorbent articles provided with a recessed groove along a longitudinal direction on a front surface have been proposed. For example, disclosed in the following Japanese Patent No. 5132264 is an absorbent article in which a high-center part located substantially in a center part of a lower layer absorber has a dent formed substantially at a center on a skin-contact surface and extending in a longitudinal direction, and a part that forms the dent of the high-center pan has a protruded pan of a lower surface of die upper layer absorber protruded toward a non-skin-contact surface and a recessed part of an upper surface of the lower layer absorber that contacts with the protruded pan and forms one body therewith, a bottom part of the dent sinks on the lower layer absorber, and both the upper layer absorber and the lower layer absorber include an absorbent fibrous material consolidated in the periphery of an uneven sunken part.
Further, in the following Japanese Patent No. 510884, an absorbent article in which a recessed part extending in a longitudinal direction of the absorbent article is integrally formed on a front surface sheet and an absorption layer is disclosed.
In Japanese Patent No. 3406214, a disposable diaper in which, between side surfaces that are formed by dividing a core and that face each other, a front surface sheet hangs down along the side surface to come into contact with a back surface sheet, and at the contact site, the front and back surface sheets are joined with each other is disclosed.
In Japanese Unexamined Patent Application No. 2007-117727A, an absorbent article in which a superabsorbent polymer is mixed in the inside of an absorber, and a part or an entirety of the superabsorbent polymer is eccentrically disposed on a peripheral wall and/or a bottom surface part of a feces pocket is disclosed.
In Japanese Patent No. 4683892, an absorbent pad is disclosed, wherein in the absorbent pad a first flexible shaft extending along a vertical axis, and a pair of second and third flexible shafts that separate to both sides in a direction of a horizontal axis from the first flexible shaft and extend in a direction of the vertical axis are located, the first flexible shaft is a penetration gutter formed by absence of an absorbent fiber between a surface that absorbs a body fluid and a surface on an opposite side, and the second and third flexible shafts are strip grooves formed by a part in which a thickness of the absorbent fiber is thinner than another part.